The present invention is in the field of hand-held plumbing tools, and has particular application in providing an improved method and apparatus for projecting a center point from one surface to another for providing alignment.
The construction of a new home or other building that is to have running water and or sewage fixtures, or the remodeling of an existing structure where an additional fixture will be installed for water or sewage, requires installation of all the various pipes necessary to carry water from the water supply to the fixtures, and subsequently drain the used water from the fixtures, as well as vent lines and pipes from waste apparatus. The matter of containing and controlling the water supply as it flows through the home or other structure is known in the art as plumbing. In a typical plumbing configuration for a home for example, pressurized water enters the home through a main supply line, usually passing through a water meter, and a portion of the incoming water is then branched off to enter a water heater. The heated water and remaining cold water are then piped to the various fixtures throughout the home. For each fixture within the home to which there is a water supply there must also be water drainage. The used cold or hot water, once passing through the fixture is typically drained into drainage pipes below the fixture, first passing through an S-shaped portion of pipe known as a trap that prevents sewer gas from drifting up through the drain. The used water than drains down, flowing by gravity, into the final sewer line where it is carried away from the home.
The drainage pipe attached to each fixture within the home or other structure must also be connected to a ventilation pipe in order to draw air from outside the home or structure to allow for proper gravity-fed drainage of the used water. In a typical plumbing configuration ventilation pipes for several fixtures are interconnected through an array of pipes to a main ventilation pipe, known in the art as a waste and vent stack. The waste and vent stack, connected to the main sewer line, usually extends from below ground level, vertically up through the structure and ultimately through a hole cut in the roof. In the case of buildings or structures with multiple floor levels, it is necessary for the waste and vent stack contained within or behind the walls, to first pass through the floor of each level, up through holes cut into the flooring material and horizontal members of the wooden framing, ultimately passing up through the roof of the structure. The portion of the waste and vent stack that penetrates the roof is known as a roof vent and can be fitted with an air filter, screen, rain shield or some other attachment.
In most buildings with running water all of the pipes used to carry water into, through, and away from the building are contained within the framework of the structure, and have a need to run in a vertical or horizontal direction in relation to the framework. The pipes are contained within the framework so that when sheet rock or other wall-covering material is applied to the framework to create walls, the plumbing pipes are hidden within the covered walls and away from view. For a drainage pipe running in a horizontal direction a slope rate, typically xe2x85x9 inch or xc2xc inch for each foot of the pipe""s length is incorporated to allow for gravity flow of the drainage water. Vertical vent, supply and drainage pipes typically have no slope rate and run within the walls parallel to the vertical members of the framework.
A plumber in conventional art is faced with a cumbersome task when attempting to determine the center point of the holes to be drilled in the framework and other materials of a structure to accommodate all of the various pipes involved. A plumber is required to manually transpose the position of a center point of a fixture where the waste and vent pipe begins, upward through multiple floors if needed, marking the, center point of the new location and making the hole through each surface. In the case of a residential structure the last horizontal portion of framework that a waste and vent pipe needs to travel through before reaching the roof is known in the art as a top-plate, and the plumbing phase that involves marking and cutting the necessary holes and extending the waste and vent pipe up through the top-plate, extending the pipe through the roof is known in the art as the top-out phase. In order to accurately place the center point for holes to be drilled or cut into members of the framework and the roof during the top-out phase, a plumber needs to first determine the center point of the line that the ventilation pipe will follow, the center point of a hole already cut into the top-plate for example, then gain access to the attic using a ladder or some other object. A plumber then needs to hold a plumb line, which is a cord or string with a lead bob or some other weighted material attached to the other end, to the underside of the roof where the new hole is to be drilled or cut in order to determine perpendicularity between the reference center point in the top-plate and the center point of the new hole to be drilled or cut into the roof.
When working with vertical drainage or vent pipes, particularly the repair or replacement of existing pipes or fixtures, the starting center point for a vertical line to be projected is typically the center of the insertion hole of a plumbing fixture, such as an elbow section for example, into which the threaded end of a newly installed vertical pipe will be inserted. A problem often encountered when plumbing vertical pipes is the top horizontal edge of the insertion hole of a plumbing fixture such as described is not always exactly perpendicular in relation to the desired vertical line to be projected. For example, to avoid installing a vertical pipe at an undesirable angle, a plumber is required to compensate for the undesirable angle of the plumbing fixture used as the starting reference point. In this example the starting reference point is the center point of the insertion hole into which a vertical pipe will be installed. After manually projecting the desired vertical line from the center point utilizing methods previously described, a plumber must then detach the fixture from any other pipes it may be attached to, correct the undesirable angle by changing the angle of the fixture or attached pipes, and then reattach the fixture at the correct angle so as to allow for the installation of the vertical pipe which follows the desired vertical projected line.
A plumber is also required to make holes through the framework of a structure to accommodate all of the horizontal pipes in the plumbing configuration. Projecting the center point of a horizontal plumbing line from one surface to another where holes are to be drilled or cut is also a cumbersome and time-consuming task using conventional methods and apparatus. Since a plumb line cannot be used in this instance, the reference center point where the line begins, the center point of an existing hole or fixture for example, must be manually transposed to new surface by first taking measurements between the starting center point and nearby objects and applying those measurements to the new surface. As previously mentioned all horizontal drainage pipes require a slope to be incorporated into the horizontal path they will follow, adding another complicated step and exacerbating the problem of manually transposing measurements from one surface to another. Other methods of projecting a horizontal line from one surface to another involve the use of vertical or horizontal carpenter""s levels, strings, tape measures, etc., methods that are also cumbersome and time-consuming in conventional art.
The methods used to project a vertical or horizontal line from one surface to another has changed little over many years in the art of plumbing, and needs to be greatly simplified for the professional plumber or layman. Much time and money can be saved by such a process that enables a user to quickly and accurately project a center point using less time, effort and tools.
What is clearly needed is an improved method and apparatus for projecting a center point that enables the utilization of an existing common plumbing fixture or an existing hole""s center point to provide a starting reference center point, and quickly and accurately projects that center point to another surface for marking. What is also clearly needed is a method and apparatus using center point projectors that compensates for undesirable slopes or angles of holes or plumbing fixtures, thus allowing for easier and more accurate projection of exactly vertical center lines from the starting reference point. Such a method and apparatus in a preferred embodiment should be compatible for use with different standard sizes of plumbing pipe fittings, pipe dimensions, as well as other tools and practices commonly known in the art. It is to these objects and others that the present invention is dedicated, and apparatus and methods are taught herein in enabling detail for accomplishing these ends.
In a preferred embodiment of the present invention, a center-point projector for determining location for alignment is provided, comprising a body having at least a first cylindrical portion with a first diameter ending in a shoulder, the first cylindrical portion having an axis; and laser pointer constrained in a cavity of the body such that the laser, when activated, projects along the axis. In some embodiments there is a switch for activating the laser pointer, and the switch may be a push-button switch, normally off. In some embodiments the switch further comprises a flexible, sealable cover.
In some embodiments there is a second cylindrical portion sharing the axis of the first cylindrical portion, the second cylindrical portion having a second diameter greater than the first diameter, which allows the device to be used with openings of differing diameters.
In another aspect of the invention, in a construction process involving plural members of an assembly, a method for projecting the axis of an opening in a first member onto a second member is provided, comprising steps of (a) positioning a laser projector having a first cylindrical portion with a first diameter ending in a shoulder, the first cylindrical portion having an axis, the laser projector having also a laser pointer constrained in a cavity of the body such that the laser, when activated, projects along the axis, into a cylindrical cavity of the first member; (b) activating the laser pointer so that the laser projects along the axis of the opening of the first member onto a remote member; and (c) marking the position of the laser projecting on the remote member.
In some embodiments of the method the first member is a plumbing fixture, and in others the first member is a construction member having a circular opening. The laser pointer may be activated by an on-off switch, which may be a push-button switch, normally off. The switch can be protected by a flexible, sealable cover.
In some embodiments the laser projector further comprises at least a second cylindrical portion sharing the axis of the first cylindrical portion, the second cylindrical portion having a second diameter greater than the first diameter, and there may be a level-indicator, with the method further comprising a step for consulting the level-indicator.
In yet another aspect of the invention a center-point projector for determining location for alignment is provided, comprising a body having at least a first cylindrical portion with a first diameter ending in a shoulder, a vertical-seeking mechanism mounted in the body, and a laser pointer mounted in the vertical-seeking mechanism. In this aspect the vertical-seeking mechanism causes the laser pointer, when activated, to seek to point vertically in the direction of action of gravity. In preferred embodiments the vertical-seeking mechanism is a weighted gimbal mechanism.
In embodiments of the invention disclosed herein in enabling detail, for the first time a projector is provided that makes the job of aligning openings in separate construction members relatively easy.